Spark-plug insulator



Feb. 17, 1931. E HUNTINGTON 1,792,985

SPARK PLUG INSULATOR Filed May 31, 1927 A TTORNEY.

Patented Feb. 17, 1931 UNITED STATES PATENT OFFICE EDWARD E. HUNTINGTON, OF TOLEDO, OHIO, ASSIGNOR TO THE WILLYS-OVERLAN COMPANY, OF TOLEDO, OHIO, A CORPORATION OF OHIO SPARK-PLUG INSULATOR Application filed May 31,

particular relation to engines wherein the spark plugs are mounted in a deep seated position, such for example, as inthe so-called Knight engines.

One of the principal objects of my invention is to overcome non-firing and miss-firing of internal combustion engines of the above designated class.

Another object of my invention is to provide an ignition system for Knight engines having a high potential secondary circuit which will give regular uninterrupted performance.

It is a further object of my invention to .provide a spark plug construction for engines having deep seated apertures to receive the plug, which obviates missing.

It is a further object of my invention to provide a modified spark plug construction for Knight engines having a small bore which is capable of operating regularly, at high engine pressures and under adverse atmospheric conditions.

Internal combustion engines, particularly those of the-Knight class, include a well portion, wherein the spark plug is mounted. It has been observed that under certain conditions engines of this class function irregularly, that is one or more of the cylinders fails to perform, resulting in what is commonly known as missing This phenomenon is observed under various operating conditions and is aggravated by moist weather conditions, excessive internal pressures, rich gas mixtures, old spark plugs and perhaps other factors. It has been noted that contrary to expectation, the more powerful the ignition system the more apparent is this missing phenomena, and excepting for this fact, the more powerful ignition systems are tobe desired.

According to my invention I have provided an insulating medium surrounding the head of the spark plug together with the connecting wire thereby eliminating these undesirable operating characteristics. I

A better understanding of the invention may be had by referring to the drawing 1927. Serial No. 195,247.

which is a sectional view of the upper portion of a Knight engine and illustrates an embodiment of my invention which may be preferred.

The drawing illustrates but a portion of a cylinder casting or block 10 showing its relation to a cylinder head 11 including a spark plug well 12 formed in the central portion of the head. It is made secure to the block 10 by means of a plurality of bolts and includes a compression ring 13 and sealing ring 14 which engage the inner of two reciprocating sleeves 1 6 and 17. A cover plate 18 extends over the major portion of the cylinder headand is retained in sealed relation. therewith by means of rubber gaskets 19. Within the spark plug well is screwed a spark plug 21 which is in communicative relation with respect to the cylinder chamber. It is of conventional design and includes an upper stem 22 and brass head 23. An insulated wire 24 from the distributor system is held in contact with the stem.

An insulating material such as bakelite is molded to form ahollow cover or protector 26 for the head and stem portion of the plug. Molded in the insulator is a cup shaped member 27, provided preferably with threads to mesh with those of the stem, and including an enlarged portion 28 which is adapted to receive a resilient member 29 that is ,secured to the end of the wire. By means of this construction the wire may be pushed into the opening in the upper portion of the insulator until the resilient portion is sprung within the enlargement of the cap member 26 where it is retained securely.

It will be noted that the manner of maintainin the wire in engaged relation with re-- 25 spark plug, a neck portion above the recess parent those skilled in the art that other insulating materials ma be utilized and other structural details may e employed without departing from the scope of the invention,

and I desire therefore that it be limited only 'asindicated in the appended claims.

I claim:v '1. The combination with the head of a Knight engine including a spark plug well,

of a spark plug, a wire connection thereto,.a dielectric member insulating the end of the plug and the wire connected therewith, said dialectric member having a lower recess surrounding the spark plug, an upper recess surrounding the wire connection coaxial with the first recess, and a restricted opening between the recesses forming a shoulder to en gage the spark plug, saidupper recess opening upwardly whereby the wire connection is supported coaxially of the-plug and in spaced relation to the'well.

2. An insulator for adapting spark plugs having threaded terminals to Knight engines, comprising a body portion having recesses adapted to receive the upper portion of the having a threaded opening adapted to screw onto the termlnal, said insulator having a second recess above the neck portion adapted to enclose and support a spark plug wire in 

